Health, the environment and the arts remained longtime favorites. The industry's next big cause, though, would focus on raising awareness, not cash. The idea was propelled by an unlikely duo: Barack Obama and John McCain. Just days after Stand Up aired, the then-presidential contenders attended a public forum held by ServiceNation, telling the advocacy group that public service and volunteerism should be national priorities.

Their bipartisan call to action morphed into "I Participate," a Hollywood-fueled initiative that's shaping up as one of TV's biggest, most innovative public service efforts ever. From next Monday to Oct. 25, ABC, NBC, CBS, Fox and several cable channels will devote chunks of more than 90 shows to mobilize viewers off their couches.

Audiences will be peppered with celebrity public service announcements (PSAs), end-of-episode pleas from casts and volunteerism segments on reality shows, talk and news programs from The View to Today. But most I Participate messages will be more subtle, weaving motivational themes and dialogue into dozens of scripted sitcoms and dramas as plot points or character-driven story lines.

"Embedding something into entertainment plants a seed that has value in ways a (PSA) doesn't. You're not beating someone over the head with it," says CSI: NY's Hill Harper, whose character, medical examiner Sheldon Hawkes, has volunteered as a first-responder physician.

Next week, viewers will see Private Practice doctors treating the homeless, Ghost Whisperer crime solvers donating blood and Gary Unmarried providing video greetings for troops overseas. "When people see a plan in action, it's much better than some talking head telling them what to do," says actress Dana Delany, whose Katherine Mayfair is among several Desperate Housewives organizing a neighborhood watch.

Initially conceived as a message platform for a handful of TV shows, I Participate has mushroomed into a campaign larger than TV's post-Katrina and 9/11 memorial and fundraising efforts, network programmers say.

"It's just heartwarming to see how everyone embraced this," says Preston Beckman, scheduling chief for Fox, which is incorporating I Participate into scripted series and PSAs for other shows, including Bones,So You Think You Can Dance and COPS. "It's great when you can find something that unites all of us, regardless of our political views."

Scripted 'aha!' moments

Brad Jamison, head of Disney/ABC corporate initiatives, expects the messages engage viewers in ways PSAs don't. "We hope there will be 'aha' moments that help people overcome perceived obstacles about doing something for others," he says. "The beauty of volunteering is you can get involved in anything."

That's the message EIF President Lisa Paulsen and former Paramount Pictures CEO Sherry Lansing got hearing Obama and McCain at the ServiceNation forum. Paulsen and EIF board Chairwoman Lansing later floated the idea to EIF directors — power brokers representing TV networks, film studios and Hollywood talent. "Everyone talked about their interests, but what was unifying was volunteerism," Paulsen says.

According to Bureau of Labor Statistics surveys, one in four Americans volunteer, a rate static for 40 years. (The Corporation for National and Community Service, the federal agency that oversees service programs, says volunteering rose 1.5% in 2008.) Lansing says I Participate, backed by partners including the AARP and Major League Baseball, will show how easy it is for more people to make an effort. "I hope giving back to society becomes part of the culture, like breathing," says Lansing, who has eschewed a sedentary retirement by co-founding Stand Up and championing charities, schools and social issues through her foundation.

Although some shows were still formulating I Participate tie-ins at press time, the initiative already has gotten TV time commitments far beyond the handful of shows EIF initially hoped for, propelled by ABC's head of scheduling, Jeff Bader. Recalling the impact Fonzie (Henry Winkler) had on getting kids to libraries after the tough guy got a library card on an episode of the '70s sitcom Happy Days, Bader suggested incorporating motivating themes into scripted shows.

"Why not use what we do best — storytelling — as a way to promote this, and do it in a way that reaches the most people," Bader says. A similar concept was embraced on a smaller scale at the channel ABC Family in September with tie-ins to service clearinghouse DoSomething.org and story lines on the college dramedy Greek. Giving back to community has also been a central theme on Family's Lincoln Heights, now in its fourth season. Says Family channel President Paul Lee; "This isn't some mandate from the top. A lot of this is driven by Millennials on staff. It resonates with them."

For I Participate, specific volunteering and public service themes were left to individual show runners and writers. "Everyone has a cause they care about, and the shows can use whatever message they want. It's about service," Bader says.

"This isn't that different from what some series already do, CBS Senior Vice President David Brownfield says. "On shows like Cold Case and Numb3rs, a half-dozen episodes would qualify for this, so I don't think viewers are going to say this seems odd."

Gary Unmarried's plot point supports the military, with 12-year-old Louise (Kathryn Newton) preparing videotaped greetings for overseas troops. The idea transcends both the character of Uncle Mitch, a Marine reservist, and actor/comedian Rob Riggle, the Marine Corps reserve officer who portrays him.

"People tend to forget the thousands of troops who've been fighting overseas for eight years," producer Ira Ungerleider says. "It's our responsibility to be supportive on the home front."

Louise will volunteer at an animal shelter in another episode. "We kind of went overboard on (I Participate), but it struck a chord," Ungerleider says.

Public service and volunteering themes were inserted so seamlessly in some shows that casts were unaware plot points were part of a broader initiative.

"We wanted to make it part of the fabric of the story, but not the story — that this is something the characters would do, that they are natural and organic to the their everyday lives," says Shonda Rhimes, creator of ABC's Grey's Anatomy (Dr. Karev gives blood) and Private Practice(doctors donate time at a homeless shelter).

Similarly, writers for NBC's 30 Rock incorporated a humorous story line for perpetual do-gooder Kenneth Parcell (Jack McBrayer), who has embraced faux charities including Pants for Zoo Animals. Next week, Parcell's animal shelter work gets him emotionally wrapped up with abandoned dogs. Says producer Matt Hubbard: "We talked about doing a bunch of things, but there was an 'aha!' moment where we realized this would tie into another funny story later in the episode. Kenneth is so moral and pure, anything he does has to be good."

McBrayer says he didn't know his "minor plot point" was part of a bigger message. "It does kind of make fun of things, but on a bigger scale, it shows there's a volunteer organization for anything, for any cause," he says.

Brothers, the new Fox sitcom starring retired NFL star and network football analyst Michael Strahan, will center on his character and sibling (Daryl "Chill" Mitchell) volunteering as high school football coaches. "You may see a (TV) character one way, but you also see how they are a giving person. If you can make it cool to volunteer, it can have a long impact," Strahan says. He also taped a PSA for Help USA, which provides homes, jobs and other services to the homeless. Strahan has supported the organization for 15 years.

Viewers may find irony in public service messages of reality shows such as NBC's Biggest Loser, where hefty contestants will be at a food bank packing goods for those who don't have enough to eat. "It's not the most natural tie-in," says Loser co-creator JD Roth of 3 Ball Productions. "But it's a great way to raise awareness of obesity while making viewers aware of millions of people who can't put food on their table."

Will audiences tune out?

On a broader level, how much impact could I Participate have?

Filmmaker Robin Baker Leacock, whose November PBS documentary A Passion for Giving examines the personal and social impact of lending help to others, says the timing of the I Participate effort is prescient, given the troubled economy, high unemployment and strapped consumers. "People are starting to see you only get so much satisfaction acquiring things and status," she says. "Helping others makes people feel good. If TV can show how people can help, even subliminally, that's great."

Others aren't sure that audiences — even through subtle product placement-style messages — won't tune out TV's volunteering themes. Mike Rowe, host of Discovery Channel's popular blue-collar reality series Dirty Jobs, says viewers may be skeptical of celebrities often seen as out of touch with mainstream Americans, no matter how well-intentioned the message.

"Someone trying to inform me or change my behavior by taking real agendas and causes and inserting them into scripted shows and character-driven propositions sounds a little icky," Rowe says. "You can't force-feed good deeds on someone. But if they can pull it off, God love 'em."

Mitch Metcalf, NBC's head of scheduling, says I Participate's intent is to inspire viewers, not "medicine that people have to gag down."

"As long as the messages are natural and organic to the shows, you have the ability to impact millions of people," he says.

Still, Leslie Lenkowsky, former head of the Corporation for National and Community Service and now professor for the Center on Philanthropy at Indiana University, notes past political and Hollywood efforts to promote volunteerism have fallen flat.

"I don't want to pour cold water over what the entertainment industry is trying to do, but we shouldn't set our sights too high," he says. "This may lead to episodic volunteering — coming out for a day of service. But the real question is, how long will it last? It's a matter of individual motivation and (non-profits) making good use of their time."

The EIF's Paulsen insists TV's short-term effort will be bolstered by a broader, but less intensive, four-year campaign, eventually branching into movies and music, along with separate efforts by the Obama administration; the president signed bipartisan legislation that expands federal support for service and volunteer programs.

Websites such as iparticipate.org and service organizations such as the AARP will track interest. "I'm confident that a year or two from now, you'll see we've moved the needle," Paulsen says.